This invention relates to a method and apparatus for supplying articles to be weighed in an automatic weighing system of the combinatorial weighing type.
There is a combinatorial weighing-type automatic weighing system known in the art for automatically obtaining a batch of articles having a weight equal or closest to a target weight. A combinatorial-type automatic weighing system in a practical use has a number of weighing machines each of which is provided with a weighing hopper. In carrying out weighing with such a system, the weighing hoppers are supplied with articles to be weighed, the weight of the articles in each weighing hopper is detected by the associated weighing machine, combinations of the weight values obtained from each of the weighing machines, as well as the total weight of each combination, are computed, a combination (referred to as the "optimum combination") whose total weight is equal or closest to a target weight is selected from among the available combinations, and only the articles in the weighing hoppers of the weighing machines corresponding to the selected optimum combination, are discharged from these weighing hoppers, whereby there is obtained a batch of articles the weight whereof is equal or closest to the target weight.
The automatic weighing system of the above-described type is equipped with a plurality of pool hoppers corresponding to and disposed above the weighing hoppers. The weighing hoppers which have discharged their articles, namely the weighing hoppers corresponding to the optimum combination, are immediately resupplied with articles by the corresponding pool hoppers, so that these weighing hoppers will be ready for the next weighing cycle. Further, the pool hoppers which are left empty by supplying their articles to the weighing hoppers, are themselves resupplied with articles distributed by a device which retains a supply of the articles.
However, with the conventional method and apparatus for supplying articles described above, it is necessary that the number of pool hoppers be the same as the number of weighing machines (weighing hoppers), and that there be provided supply means such as vibratory troughs for supplying each and every pool hopper with articles. Accordingly, the conventional automatic weighing apparatus has a large number of component parts, is complex in construction and high in cost.